Clamping system with foldable tabs for connecting tubes together

Abstract

The clamping system comprises a collar that comprises a belt suitable for being clamped around clamping surfaces projecting from tubes. The collar carries a series of angularly distributed foldable fingers, each finger presenting a free operating end projecting axially beyond the first edge of the belt over a distance that is sufficient to enable it to be manipulated by hand. Starting from an initial position in which the fingers define a rest minimum diameter, the fingers are suitable for being folded manually and plastically towards the axis of the belt in order to define a folded-in minimum diameter that is less than said rest minimum diameter.

The invention claimed is: 
     
       1. A clamping system for connecting together a first tube and a second tube having facing ends presenting clamping surfaces projecting relative to the cylindrical outside surfaces of said tubes, the system comprising a collar that comprises a belt suitable for being clamped around said clamping surfaces and a washer carried by the collar, the belt presenting first and second flanks between which there is defined an inner setback suitable for receiving the clamping surfaces, an angularly distributed series of foldable fingers projecting from the washer, each finger of the series presenting a free operating end projecting axially beyond a first edge of the belt over a distance that is sufficient to enable said each finger to be manipulated by hand, the fingers being suitable, starting from an initial position in which said fingers define a rest minimum diameter, for being folded manually and plastically towards an axis of the belt in order to define a folded-in minimum diameter that is less than said rest minimum diameter. 
     
     
       2. A clamping system according to  claim 1 , wherein each finger presents one or more first undulation with a convex side facing towards the axis of the belt and with respective positions of vertex of said undulation defining said minimum diameters. 
     
     
       3. A clamping system according to  claim 2 , wherein each finger also presents one or more second undulation that is situated between the first undulation and the inner end of the finger remote from the free end of the finger, and having a concave side facing towards the axis of the belt. 
     
     
       4. A clamping system according to  claim 1 , wherein one or more of the fingers of the series presents a longitudinal spline. 
     
     
       5. A clamping system according to  claim 1 , wherein the length by which the fingers project beyond the first edge of the belt is 5 mm or more. 
     
     
       6. A clamping system according to  claim 1 , wherein the width of the fingers, at least in zones projecting beyond the first edge of the belt, is 5 mm or more. 
     
     
       7. A clamping system according to  claim 1 , wherein the washer presents fastener tabs that co-operate with the collar. 
     
     
       8. A clamping system according to  claim 7 , wherein the fingers are integral with the washer. 
     
     
       9. A clamping system according to  claim 1 , wherein an annular gap is left between the second flank and the washer, and the fingers extend from the washer towards the first flank and beyond the first flank. 
     
     
       10. A clamping system according to  claim 9 , wherein the washer presents elastically deformable pre-mounting tabs that are suitable, in the non-clamped state of the belt, for retaining the collar relative to the second tube when the bearing surface of said second tube is engaged in the inner setback. 
     
     
       11. An assembly comprising a clamping system according to  claim 1 , together with a first tube and a second tube having facing ends presenting clamping surfaces projecting relative to cylindrical outside surfaces of said first tube and second tube, in which assembly the rest minimum diameter is not less than the maximum diameter of the clamping surface of the first tube, while said folded-in minimum diameter is less than said maximum diameter, such that the folded-in fingers retain the collar relative to the clamping surface of the first tube when said clamping surface is engaged in the inner setback. 
     
     
       12. A mounting method for mounting an assembly comprising a clamping system according to  claim 1  together with a first tube and a second tube having facing ends presenting the clamping surfaces projecting relative to cylindrical outside surfaces, in which method the free end of the first tube is engaged in the inner setback from the first edge of the belt while the fingers are in their initial position, until the clamping surface of the first tube penetrates into the inner setback, and then the fingers are turned down behind the clamping surface of the first tube in order to retain the clamping system against the first tube disengaging in the direction opposite to the engagement direction. 
     
     
       13. A mounting method according to  claim 12 , wherein the clamping system is according to  claim 10 , and wherein the free end of the second tube is engaged initially in the inner setback from the second edge of the belt until said free end penetrates into the annular gap left between the second flank and the belt.